Generally, the need to control access to outside telephone lines in an institutional environment is well recognized. In order to prevent individuals from incurring large, unaccountable telephone costs which the institution ultimately bears, one must either restrict access to outside telephone lines or institute accounting controls whereby the costs of unauthorized calls can be billed to the responsible individuals.
Telephone systems in correctional environments require additional security considerations. Without appropriate controls on telephone access, inmates have been known to use the telephones to harass outside parties (such as witnesses who testified against them, attorneys who prosecuted their case, employees of the courts, etc.), to perpetrate fraudulent schemes, and to participate in criminal conspiracies (such as arranging the smuggling of contraband into the prison, directing an outside criminal enterprise, plotting escape attempts or credit card fraud). Therefore, it is critically important for correctional management officials to carefully plan, control, monitor and record inmate access to outside telephone lines.
One of the most fundamental problems--which exists both in correctional and other business-oriented institutions--is cost control. To achieve cost control, it is critical that there be individual accountability for each call that incurs a charge to the institution. Such accountability is typically achieved through use of personal identification numbers ("pins"). Before making a call from an institution telephone, an individual must enter his PIN. The telephone service provider is then able to deliver to the institution an end-of-the-month telephone bill which lists, in addition to the cost of each call, the PIN or name of the individual who made the call. From this information, the institution can then collect reimbursement from individuals for the costs of certain calls.
While this system of end-of-the-month call accounting functions reasonably effectively in a business like environment, it does not work well in a penal institution. The reason is that inmates show little concern for phone bills they can't afford to pay. Thus, the institution is often forced to absorb the costs of phone calls by its delinquent inmates. Moreover, the fact that account balances are only computed periodically--i.e., every month, week, or even every day--permits the inmate to accrue large, uncollectible phone bills before his access to the phones can be terminated. Traditionally, penal institutions have addressed this problem by restricting inmates to collect calls only. This, however, still provides the inmates with relatively unlimited access to the outside world, leaving open numerous opportunities for fraudulent and criminal activity, as explained below. Therefore, in a penal environment, it is highly desirable to regulate phone access on an individual, pay-in-advance basis, and to immediately and automatically terminate an individual's phone access when his/her paid-up account reaches a zero balance.
Another problem in penal institutions is the inmates' desire to make threatening or harassing phone calls to witnesses, prosecutors, police officers, parol officers, psychologists, judges, and the relatives and family of such persons. Limiting the inmates' access to collect calls only does not effectively address this problem, since an inmate can easily identify himself (to an operator) as someone from whom the recipient would likely accept a collect call. Rather, one should, at a minimum, provide a means that permits a potential call recipient to identify the caller as an inmate before accepting the call, whether that call is placed on a prepaid or collect basis. Conventionally, this is done by initially placing the inmate on hold and playing a prerecorded message telling the recipient that a call has been placed from a correctional facility and that, if the recipient wishes not to receive the call, he/she should hang up before the call is connected. This approach mitigates, but does not fully solve, the harassment problem. In particular, it is still possible for an inmate to repetitively call an outside party; even if the recipient hangs up after hearing the pre-recorded message, the harassing effect of receiving repetitive calls from inside the correctional institution remains. Therefore, it would be highly desirable to provide an institutional telephone system that automatically prohibits inmates from attempting to call certain outside persons. Moreover, it would also be highly desirable to provide a method and apparatus for allowing a recipient of an undesired call from an inmate to easily and automatically prohibit all future calls from that particular inmate, or from all inmates generally.
Still another concern in correctional institutions is the regulation of access to telephone systems. For various security and management reasons, it often desirable to restrict a given inmate's telephone access to particular phones, calling times, and to limit the length of calls, number of calls, and number of calls to the same number. Also, to enhance security and discipline, it should be possible to instantaneously revoke an inmate's calling privileges, or to otherwise modify the extent of a particular inmate's calling privileges.
Correctional institutions also typically wish to monitor and/or record outgoing calls. Inmate-to-attorney calls, however, cannot legally be monitored or recorded. Moreover, certain inmates--those who represent particular security risks--deserve live monitoring, as opposed to mere recording. Thus, it would be highly desirable to have a system which automatically initiates the appropriate monitoring and/or recording depending upon the identity of the inmate placing a call and the recipient of the call (i.e., attorney or non-attorney). Likewise, it may be desirable that calls to certain numbers are to be monitored live, while others need only be recorded.
Because the message content of inmate-to-attorney calls cannot be legally recorded or monitored, such calls can serve as a conduit for the inmate's illegal telephone activity. Therefore, it would be highly desirable to have a system which could passively--that is, without in any way monitoring or recording what is actually being said--monitor inmate-to-attorney calls to ensure that: (1) the only two people speaking on the line are the inmate and attorney, and/or (2) no DTMF tones, rapid line impedance changes, off-hook conditions or voltage spikes appear on the line. Techniques for voice identification are known--i.e. U.S. Pat. Nos. 4,993,068, entitled UNFORGEABLE PERSONAL IDENTIFICATION SYSTEM and 5,150,357, entitled INTEGRATED COMMUNICATIONS SYSTEM, both incorporated herein by reference--but have not been previously used in penal telecommunications applications.